Enhancing oil-water separation performance through surface engineering of 3D-printed polypropylene membranes

Abstract

Abstract Superhydrophobic porous membranes are materials that are used for oil-water separation. However, conventional fabrication methods present limited scalability, complex processing, and poor membrane morphology control. In this study, a modular alternative based on 3D printed membrane was investigated. Microporous membranes, composed of polypropylene (PP)/graphene nanocomposites, were fabricated by the fused filament fabrication (FFF) method and subsequently surface-modified via dip-coating, using coatings based on polydimethylsiloxane (PDMS), silica nanoparticles, and/or graphene nanosheets. Untreated pure PP membranes exhibited a water contact angle (WCA) of 117.9°, which increased to 123.3° when graphene was incorporated into the PP matrix. Besides, the surface treatment increased the membranes’ WCA up to 132.59°. Filtration tests demonstrated high oil-water separation efficiency, achieving up to 99%. These results highlight the synergism between additive manufacturing and nanostructured surface treatments.